Just spoke with Alliance Powders. I explained everything that I'm experiencing and testing. He agreed but doesn't have a lot of data on the 6mm Creedmoor. Mostly 6.5 with is not the same. The weight of the bullet on the 6 5 is heavier and just bigger in dia so the burn rate is different. As we spoke I'm going to try increasing the burn rate of the RL23, in the case itself by running maybe tighter next tension, going to a 115 grn bullet and running the bullet closer to the lands or into the lands. Currently I think that what's going on is that it's not burning in the case, but rather throwing the powder into the barrel and igniting there causing more heat in the barrel itself.Higher pressure/velocity and groups went from the .3s to .5s